• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.98-133
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• 1987

The mechanical and rheological properties of agricultural materials are important for engineering design and analysis of their mechanical harvesting, handling, transporting and processing systems. Agricultural materials, which composed of structural members and fluids do not react in a purely elastic manner, and their response when subjected to stress and strain is a combination of elastic and viscous behavior so called viscoelastic behavior. Many researchers have conducted studies on the mechanical and rheological properties of the various agricultural products, but a few researcher has studied those properties of rice plant, and also those data are available only for foreign varieties of rice plant. This study are conducted to experimentally determine the mechanical and the rheological properties such as axial compressive strength, tensile strength, bending and shear strength, stress relaxation and creep behavior of rice stems, and grain detachment strength. The rheological models for the rice stem were developed from the test data. The shearing characteristics were examined at some different levels of portion, cross-sectional area, moisture content of rice stem and shearing angle. The results obtained from this study were summarized as follows 1. The mechanical properties of the stems of the J aponica types were greater than those of the Indica ${\times}$ Japonica hybrid in compression, tension, bendingand shearing. 2. The mean value of the compressive force was 80.5 N in the Japonica types and 55.5 N in the Indica ${\times}$ Japonica hybrid which was about 70 percent to that of the Japonica types, and then the value increased progressively at the lower portion of the stems generally. 3. The average tensile force was about 226.6 N in the Japonica types and 123.6 N in the Indica ${\times}$ Japonica hybrid which was about 55 percent to that of the Japonica types. 4. The bending moment was $0.19N{\cdot}m$ in the Japonica types and $0.13N{\cdot}m$ in the Indica ${\times}$ Japonica hybrid which was 68 percent to that of the Japonica types and the bending strength was 7.7 MPa in the Japonica types and 6.5 MPa in the Indica ${\times}$ Japonica hybrid respectively. 5. The shearing force was 141.1 N in Jinju, the Japonica type and 101.4 N in Taebaeg, the Indica ${\times}$ Japonica hybrid which was 72 percent to that of Jinju, and the shearing strength of Taebaeg was 63 percent to that of Jinju. 6. The shearing force and the shearing energy along the stem portion in Jinju increased progressively together at the lower portions, meanwhile in Taebaeg the shearing force showed the maximum value at the intermediate portion and the shearing energy was the greatest at the portion of 21 cm from the ground level, and also the shearing strength and the shearing energy per unit cross-sectional area of the stem were the greater values at the intermediate portion than at any other portions. 7. The shearing force and the shearing energy increased with increase of the cross-sectional area of the rice stem and with decrease of the shearing angie from $90^{\circ}$ to $50^{\circ}$. 8. The shearing forces showed the minimum values of 110 N at Jinju and of 60 N at Taebaeg, the shearing energy at the moisture content decreased about 15 percent point from initial moisture content showed value of 50 mJ in Jinju and of 30 mJ in Taebaeg, respectively. 9. The stress relaxation behavior could be described by the generalized Maxwell model and also the compression creep behavior by Burger's model, respectively in the rice stem. 10. With increase of loading rate, the stress relaxation intensity increased, meanwhile the relaxation time and residual stress decreased. 11. In the compression creep test, the logarithmic creep occured at the stress less than 2.0 MPa and the steady-state creep at the stress larger than 2.0 MPa. 12. The stress level had not a significant effect on the relaxation time, while the relaxation intensity and residual stress increased with increase of the stress level. 13. In the compression creep test of the rice stem, the instantaneous elastic modulus of Burger's model showed the range of 60 to 80 MPa and the viscosities of the free dashpot were very large numerical value which was well explained that the rice stem was viscoelastic material. 14. The tensile detachment forces were about 1.7 to 2.3 N in the Japonica types while about 1.0 to 1.3 N in Indica ${\times}$ Japonica hybrid corresponding to 58 percent of Japonica types, and the bending detachment forces were about 0.6 to 1.1 N corresponding to 30 to 50 percent of the tensile detachment forces, and the bending detachment of the Indica ${\times}$ Japonica hybrid was 0.1 to 0.3 N which was 7 to 21 percent of Japonica types. 15. The detachment force of the lower portion was little bigger than that of the upper portion in a penicle and was not significantly affected by the harvesting period from September 28 to October 20. 16. The tensile and bending detachment forces decreased with decrease of the moisture content from 23 to 13 percent (w.b.) by the natural drying, and the decreasing rate of detachment forces along the moisture content was the greater in the bending detachment force than the tensile detachment force.

• Journal of Life Science
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• v.13 no.3
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• pp.280-290
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• 2003

The incorporation of RAPD markers into the previous classical and RFLP genetic linkage maps will facilitate the generation of a detailed genetic map by compensating for the lack of one type of marker in the region of interest. The objective of this paper was to present features we observed when we associated RAPD map from an intraspecific cross of a Glycine max$\times$G. max, 'Essex'$\times$PI 437654 with the public RFLP map developed from an interspecific cross of G. max$\times$G. soja. Among 27 linkage groups of RAPD map, eight linkage groups contained probe/enzyme combination RFLP markers, which allowed us the incorporation of RAPD markers into the public RFLP map. Map position rearrangement was observed. In incorporating L.G.C-3 into the public RFLP linkage group a1 and a2, both pSAC3 and pA136 region, and pA170/EcoRV and pB170/HindIII region were in opposite order, respectively. And, pk400 was localized 1.8 cM from pA96-1 and 8.4 cM from pB172 in the public RFLP map, but was localized 9.9 cM from i locus and 18.9 cM from pA85 in our study. A noticeable expansion of the map distances in the intraspecific cross of Essex and PI 437654 was also observed. Map distance between probes pA890 and pK493 in L.G.C-1 was 48.6 cM, but it was only 13.3 cM in the public RFLP map. The distances from the probe pB32-2 to pA670 and from pA670 to pA668 in L.G. C-2 were 50.9 cM and 31.7 cM, but they were 35.9 cM and 13.5 cM in the public RFLP map. The detection of duplicate loci from the same probe that were mapped on the same or/and different linkage group was another feature we observed.

• The Journal of Engineering Geology
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• v.19 no.4
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• pp.517-528
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• 2009

Statistical analyses of cut-slope stability were performed over approximately 5.7 km section along the National road No. 25, which cross-cuts in NW-SE direction the Cheongwon and Boeun-Gun area, Chungbuk. A measure of slope-stability was established by using direct reinforcement and indirect protection methods in whole section. Orientations(dip/dip direction) of the slopes, foliations(bedding), cleavages and joints were measured in total of 30 slope sites. The results analyzed using stereographic projection indicate that major directions of the slopes come out predominantly in three directions: 1) $58^{\circ}/095^{\circ}$, 2) $60^{\circ}/296^{\circ}$ and 3) $59^{\circ}/212^{\circ}$. In analyses of dip direction and frequency of cut-slopes established by reinforcement and protection methods, slopes with dip direction of $80-120^{\circ}$ and $280-320^{\circ}$ mostly occur. However, slopes with dip direction of $0-80^{\circ}$(N and NW) and $120-160^{\circ}$(SE) are not distributed in the study area. Failure aspects were analyzed for three major directions of the slopes, respectively. The results of failure aspects analyzed indicate that slopes in the study area could generate various failures as the results of intersection and/or intersection combination among joints, foliations(bedding) and cleavages. However, possibility of failure in a slope of major direction No. 3 is statistically very low because of low frequency in total number of slopes with the direction and of formation of small scale-slopes geographically, although the slope might generate all aspects of failure-modes.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2627-2630
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• 2013

Background: Ovarian cancer continues to pose a major challenge to physicians and radiologists. It is the third most common gynecologic malignancy and estimated to be fifth leading cancer cause of death in women, constituting 23% of all gynecological malignancies. Multi-detector computed tomography (MDCT) appears to offer an excellent modality in diagnosing ovarian cancer based on combination of its availability, meticulous technique, efficacy and familiarity of radiologists and physicians. The aim of this study was to compute sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of 64-slice MDCT in classifying ovarian masses; 95% confidence intervals were reported. Materials and Methods: We prospectively designed a cross-sectional analytical study to collect data from July 2010 to August 2011 from a tertiary care hospital in Karachi, Pakistan. A sample of 105 women aged between 15-80 years referred for 64-MDCT of abdomen and pelvis with clinical suspicion of malignant ovarian cancer, irrespective of stage of disease, were enrolled by non-probability purposive sampling. All patients who were already known cases of histologically proven ovarian carcinoma and having some contraindication to radiation or iodinated contrast media were excluded. Results: Our prospective study reports sensitivity, specificity; positive and negative predictive values with 95%CI and accuracy were computed. Kappa was calculated to report agreement among the two radiologists. For reader A, MDCT was found to have 92% (0.83, 0.97) sensitivity and 86.7% (0.68, 0.96) specificity, while PPV and NPV were 94.5% (0.86, 0.98) and 86.7% (0.63, 0.92), respectively. Accuracy reported by reader A was 90.5%. For reader B, sensitivity, specificity, PPV and NPV were 94.6% (0.86, 0.98) 90% (0.72, 0.97) 96% (0.88, 0.99) and 87.1% (0.69, 0.95) respectively. Accuracy computed by reader B was 93.3%. Excellent agreement was found between the two radiologists with a significant kappa value of 0.887. Conclusion: Based on our study results, we conclude MDCT is a reliable imaging modality in diagnosis of ovarian masses accurately with insignificant interobserver variability.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.659-664
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• 2013

The aim of this study is to determine the drought stress index through photochemical analysis in red pepper (Capsiumannuum L.). The photochemical interpretation was performed in the basis of the relation between Kautsky effect and Photosystem II (PSII) following the measurement of chlorophyll, pheophytin contents, and $CO_2$ assimilation in drought stressed 5-week-old red pepper plants. The $CO_2$ assimilation rate was severely lowered with almost 77% reduction of chlorophyll and pheophytin contents at four days after non-irrigation. It was clearly observed that the chlorophyll fluorescence intensity rose from a minimum level (the O level), in less than one second, to a maximum level (the P-level) via two intermediate steps labeled J and I (OJIP process). Drought factor index (DFI) was also calculated using measured OJIP parameters. The DFI was -0.22, meaning not only the initial inhibition of PSII but also sequential inhibition of PSI. In real, most of all photochemical parameters such as quantum yield of the electron transport flux from Quinone A ($Q_A$) to Quinone B ($Q_B$), quantum yield of the electron transport flux until the PSI electron acceptors, quantum yield of the electron transport flux until the PSI electron acceptors, average absorbed photon flux per PSII reaction center, and electron transport flux until PSI acceptors per cross section were profoundly reduced except number of QA reducing reaction centers (RCs) per PSII antenna chlorophyll (RC/ABS). It was illuminated that at least 6 parameters related with quantum yield/efficiency and specific energy fluxes (per active PSII RC) could be applied to be used as the drought stress index. Furthermore, in the combination of parameters, driving forces (DF) for photochemical activity could be deduced from the performance index (PI) for energy conservation from photons absorbed by PSII antenna until the reduction of PSI acceptors. In conclusion, photochemical responses and their related parameters can be used as physiological DFI.

• Journal of Life Science
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• v.22 no.2
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• pp.148-155
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• 2012

A cross-sectional analysis of blood pressure (BP) changes and the current prevalence and distribution of hypertension among age groups in Korea were conducted. Systolic (SBP), diastolic (DBP), and pulse (PP) pressures were evaluated. Residents visiting a local Community Health Center for a health check-up and/or participating in the Health Promotion Program were included for the analyses. A total of 6,570 subjects (2,809 men, 3,761 women) were divided into five age groups: 30-39, 40-49, 50-59, 60-69, and $70\leq$ years. Comparisons were made between sex and among age groups. SBP and DBP were continuously elevated, while men showed higher levels than women until their mid-60s; then, the trend was reversed. DBP in men became elevated from their 30s, reaching the highest in the 40s then slowly decreasing. DBP in women increased up to their 40s and 50s, then reached a plateau. PP increased rapidly from the 50s in both sexes. The major contributor of age-related BP elevation may be large artery stiffness in men, particularly from their 50s, while the blood pressure elevation of women may relate to diverse factors including large artery stiffness, stroke volume, and ventricular ejection rate. The rapid elevation of PP after the 50s in both men and women could represent a risk of cardiovascular or coronary mortality, particularly with increasing age. The current data showed a higher rate of hypertension in both sexes compared to previous reports. When those with both high-normal BP and hypertension are looked at in combination, BP management of the target population should be drastically elevated.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.6883-6888
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• 2015

Background: Tobacco smoking is a major cause of preventable disease and death worldwide. Kreteks are clove-flavored cigarettes made from a combination of tobacco and ground-clove mixed with a sauce, smoked widely in Indonesia. Because health and social consequences of kretek smoking are potentially as great as those of traditional cigarettes, this study examines the prevalence of kretek smoking in Indonesia and associated risk factors. Materials and Methods: The study used nationally representative Indonesia Global Adult Tobacco Survey data. Multiple logistic regression analysis was employed to identify correlates of kretek smoking. Results: One-third of Indonesian adults smoked tobacco of which about 90.0% smoked kreteks. Prevalence of kretek smoking among men (60.9%) was more than 25 times the rate among women (2.3%). Overall, the highest prevalence of kretek use was in the age group 45-54 years (36.5%), followed by 34-44 (35.1%), 25-34 (34.2 %), and 55-64 years (32.8%). By wealth index, prevalence of kreteks smoking among those in the middle index was almost 50% above the rate for the wealthiest group (36.4% vs 24.8% respectively). Logistic regression results showed that being male, being older, having less education, and being less wealthy were significant predictors of kretek smoking, while urban vs rural residence was not. Conclusions: Kretek smoking is common in Indonesia and is entrenched in the sociocultural fabric of the country. However, potential consequences of kretek smoking, particularly as risks for noncommunicable diseases, underscore the importance of a comprehensive approach to tobacco control as outlined in the World Health Organization's MPOWER strategies.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.2
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• pp.192-209
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• 2004

Purpose : The purpose of this study was to evaluate the machining accuracy and consistency of implant/abutment/screw combination or internal connection type. Material and methods: In this study, each two randomly selected internal implant fixtures from ITI, 3i, Avana, Bicon, Friadent, Astra, and Paragon system were used. Each abutment was connected to the implant with 32Ncm torque value using a digital torque controller or tapping. All samples were cross-sectioned with grinder-polisher unit (Omnilap 2000 SBT Inc) after embeded in liquid unsaturated polyester (Epovia, Cray Valley Inc). Then optical microscopic and scanning electron microscopic(SEM) evaluations of the implant-abutment interfaces were conducted to assess quality of fit between the mating components. Results : 1) Generally, the geometry of the internal connection system provided for a precision fit of the implant/abutment into interface. 2) The most precision fit of the implant/abutment interface was provided in the case of Bicon System which has not screw. 3) The fit of the implant/abutment interface was usually good in the case of ITI, 3I and Avana system and the amount of fit of the implant/abutment interface was similar to each other. 4) The fit of the implant/abutment interface was usually good in the case of Friadent, Astra and Paragon system. The case of Astra system with the inclined contacting surface had the most Intimate contact among them. 5) Amount of intimate contact in the abutment screw thread to the mating fixture was larger in assembly with two-piece type which is separated screw from abutment such as Friadent, Astra and Paragon system than in that with one-piece type which is not seperated screw from abutment such as ITI, 3I and Avana system. 6) Amount of contact in the screw and the screw seat of abutment was larger in assembly of Friadent system than in asembly of Astra system of Paragon system. Conclusion: Although a little variation in machining accuracy and consistency was noted in the samples, important features of all internal connection systems were the deep, internal implant-abutment connections which provides intimate contact with the implant walls to resist micro-movement, resulting in a strong stable interface. From the results of this study, further research of the stress distribution according to the design of internal connection system will be required.

• BMB Reports
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• v.45 no.9
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• pp.509-514
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• 2012

We have found that the previously uncharacterized bone morphogenetic protein-9 (BMP9) is one of the most osteogenic factors. However, it is unclear if BMP9 cross-talks with $TGF{\beta}1$ during osteogenic differentiation. Using the recombinant BMP9 adenovirus, we find that low concentration of rh$TGF{\beta}1$ synergistically induces alkaline phosphatase activity in BMP9-transduced C3H10T1/2 cells and produces more pronounced matrix mineralization. However, higher concentrations of $TGF{\beta}1$ inhibit BMP9-induced osteogenic activity. Real-time PCR and Western blotting indicate that BMP9 in combination with low dose of $TGF{\beta}1$ potentiates the expression of later osteogenic markers osteopontin, osteocalcin and collagen type 1 (COL1a2), while higher concentrations of $TGF{\beta}1$ decrease the expression of osteopontin and osteocalcin but not COL1a2. Cell cycle analysis reveals that $TGF{\beta}1$ inhibits C3H10T1/2 proliferation in BMP9-induced osteogenesis and restricts the cells in $G_0/G_1$ phase. Our findings strongly suggest that $TGF{\beta}1$ may exert a biphasic effect on BMP9-induced osteogenic differentiation of mesenchymal stem cells.

• Journal of Preventive Medicine and Public Health
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• v.32 no.4
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• pp.505-512
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• 1999

Objectives : The purpose of this study was to assess the relationship between job strains and absenteeism from work. Methods : The study design was cross-sectional, and the study subjects consisted of 1,166 workers who were employed in the small-sized industries. A self administered questionnaire was used to measure the general characteristics, job characteristics(job demand, job control), and social support(coworker support, supervisor support) at work. The Job Content Questionnaire(JCQ) was used to assess job demand(2 items) and decision lattitude(10 items). Social support at work (10 items) was measured using JCQ. Sick absence was collected using self-report and were rechecked by the attendance record of their company. Odds ratios and 95% confidence intervals for the association between job strain and sick absence were estimated. The modifying effect of social support was evaluated by stratification. Logistic regression was used to estimate the relationship between job strain and sick absence. Results : In the bivariate analysis, the variables related to sick absence were age, marital status, occupation, job demand. Four distinctly different kinds of level of job strain were generated by the combination of job demand and job control: low strain group, high strain group, active group, and passive group. The crude odds ratio of high job strain was 1.78(95% CI: 1.26-2.53), and those of active group and passive group were 1.33(95% CI: 1.07-1.66) and 1.13 (95% CI: 0.88-1.47), respectively. The odds ratio of high job strain after adjusting for age and occupation were still significant The odds ratio of high job strain in low social support was 5.96(95% CI: 2.45-14.51), but that in high social support was 0.73(95% CI: 0.26-2.01). Conclusions : Job strain was associated with increased risk of absenteeism from work, and social support at work modified the association between job strain and sick absence.